1. Field of the Invention
The present invention relates to a cushioning device for umbrella, which is attached to a runner of an umbrella to change the magnitude of force that drives the runner to slide along a central post through a simple regulation operation so as to make an umbrella opening operation gentle and safe.
2. The Related Arts
The opening operation of an umbrella is generally carried out by having a runner driving a plurality of ribs upward to open a canopy. Since such an upward movement of the runner requires a great force to open the canopy, an energy device is often provided in the umbrella to increase the kinetic energy applied to the runner. For example, springs are mounted to the ribs to help opening the canopy, or a spring is added to the central post to increase the moving speed of the runner in opening the umbrella.
Increasing the moving speed of the runner in opening the umbrella cause undesired side effect of potential risk of hurting a person standing by the umbrella due to the ribs are fast expanded in a very short period of time, which may have tips of ribs entangling the clothes of the person or impacting the person. Additionally, the fast expansion of the ribs may scare people standing around. Such a problem is often found in the operation of automatic umbrellas.